<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <script src="../js/vue.js"></script>
</head>
<body>
    <div id="app">
        <input type="text" v-focus="true">
    </div>
    <script>
        Vue.directive('focus',{
            inserted(el,binding){
                console.log('页面元素插入');
                console.log(binding);
                if(binding.value){
                    el.focus();
                }
            }
        });
        var vm = new Vue({
            el:'#app'
        });
    </script>
</body>
</html>